Where do you focus with t-grain films? Not sure if this is a question for this subforum or the B&W film and paper group but here goes:
I used to print ages ago but back then I never used t-grain films, just traditional ones. Now I've been shooting some of both, HP5+ and FP4+ which I always used and enjoyed and some Delta of various speeds as well. Since the time when I used to do darkroom before I mostly had others do the dev and printing so I didn't look for this but now that I'm doing both myself again I guess I'm finally paying attention and I noticed that e.g. HP5+ has a flat 2-D grain structure while the Delta 400 and 3200 films have a deeper 3-D structure. Delta 100 is fairly tight and the grain is very small anyways so this is more a question about the fast films.
Back to my question, with HP5+ it is obvious where to focus using the grain 'scope, as you move the focus the whole 2-D structure comes into focus essentially at once. With the fast Delta films instead there is a 3-D lattice which comes into focus. Do I aim for the middle of this, the top, the bottom? Does it really matter if I'm going to stop the El-Nikkor down to f/8 anyways?